Over 170 Separex™ membrane systems have been installed in the world for gas separation applications such as for the removal of acid gases from natural gas, in enhanced oil recovery, and hydrogen purification. Two new Separex™ membranes (Flux+ and Select) have been commercialized recently by Honeywell UOP, Des Plaines, Ill. for carbon dioxide removal from natural gas. These Separex™ spiral wound membrane systems currently hold the membrane market leadership for natural gas upgrading. These membranes, however, are not suitable for water purification applications. Development of new stable, high flux, and high rejection membranes is critical for the future success of membranes for liquid phase separations such as water purification.
Reverse osmosis (RO) and nanofiltration (NF) membranes are the current most important technologies for water desalination and purification and they are experiencing significant growth. High fouling resistant, high flux and high selectivity RO and NF membranes will offer more opportunities for using membrane technology for water treatment applications.